Interesting timing on this - I wasn't in Phoenix obviously but last Thursday I had something pretty similar over Pendle Hill around 11pm. Three lights in a loose triangular formation, very slow moving, no sound at all. What gets me is the silence, because anything that size moving that slow should be making some kind of noise shouldn't it?
Did yours hold a fixed formation the whole time or did the lights shift relative to each other? Mine seemed to maintain the shape almost perfectly which rules out birds or drones in my head. Also what altitude would you estimate? Hard to judge but these felt low, maybe a few hundred feet.
I've been into UAP stuff for years and the triangular formation is one of the more consistently reported patterns globally. Would be genuinely useful to compare notes if the sightings share characteristics despite being different locations and presumably unrelated.
